Immunotherapy for Gestational Trophoblastic Neoplasia: A New Paradigm

Mixed Gestational Trophoblastic Tumors-Challenging Clinicopathological Presentations

Mixed gestational trophoblastic tumors are exceptionally rare and have variable clinicopathological presentations. We report 3 such tumors with different combinations of choriocarcinoma (CC), placental site trophoblastic tumor (PSTT), and epithelioid trophoblastic tumor (ETT). The patients' age ranged from 38 to 44 years. Mixed trophoblastic tumor was not considered at the initial diagnosis and all 3 tumors were proven of gestational origin by DNA genotyping. Patient #1 presented with serum human chorionic gonadotropin (hCG) of 97 mIU/mL and a 5.6-cm cervical mass that was initially interpreted as PSTT on biopsy. Hysterectomy revealed a mixed PSTT (60%) and ETT (40%) with extrauterine metastases of only the ETT component. The tumor recurred 15 months after a multiagent chemotherapy and was tested positive for programmed death-ligand 1. The patient received immune checkpoint inhibitor therapy and remained disease-free after 24 months. Patient #2 presented with vaginal bleeding and serum hCG of 46,458 mIU/mL. An endometrial biopsy was interpreted as CC. Recurrence developed in the uterus and lung after methotrexate-based chemotherapy. A mixed CC and ETT were eventually diagnosed upon consultation review. Patient #3 presented with a complete hydatidiform mole and serum hCG of 744,828 mIU/mL. Three months after methotrexate, followed by actinomycin D therapy, a uterine mass was found. Hysterectomy revealed a mixed CC and PSTT. In conclusion, the rarity, elusive presentation, and wide range of histology make the diagnosis of mixed trophoblastic tumors highly challenging. The clinical management and prognosis are dictated by each component of the tumor. CC component must be considered when the patient presents with a high serum hCG level.

Case report: Multidrug resistant gestational trophoblastic neoplasia: focus on failure of immunotherapy and success of high-dose chemotherapy

Gestational trophoblastic neoplasia (GTN) is extremely rare, but has a very good prognosis, with a cure rate close to 100%, for low-risk diseases. This article describes the case of a healthy 28-year-old nulliparous patient with GTN resistant to multiple lines of treatment. The era of immunotherapy is revolutionizing oncology, having already proved its worth in the treatment of many cancers. This article will have a specific focus on the emerging role of immunotherapy in the treatment of GTN. Unfortunately, the use of an immune checkpoint inhibitor (ICI) failed in our case, emphasizing on the necessity to clearly define the future role of immune therapy in GTN. Finally, given the rapid progression of the disease after hysterectomy, induction with Paclitaxel- Ifosfamide and then intensification with high-dose Carboplatin and Etoposide with peripheral blood stem cell support was given as a rescue therapy with still curative intent.

Molecular profiling of gestational trophoblastic neoplasia: Identifying therapeutic targets

OBJECTIVE

The treatment for high risk or recurrent gestational trophoblastic neoplasia (GTN) is a highly toxic multi-agent chemotherapy. For patients with progressive or recurrent GTN, checkpoint inhibitors have demonstrated anti-tumor activity; however, identification of novel therapies for GTN remain an unmet need. Therefore, we sought to characterize the molecular landscape of GTN to identify potential therapeutic targets.

METHODS

GTN samples were analyzed using a combination of molecular - next-generation sequencing (NGS) or whole exome sequencing (WES)- and protein- Immunohistochemistry (IHC) analyses. GTN samples encompassed complete moles, choriocarcinoma, epithelioid trophoblastic tumors (ETT), and placental site trophoblastic tumors (PSTT).

RESULTS

We analyzed 30 cases of GTN including 15 choriocarcinoma, 7 ETT, 5 PSTT, 1 invasive mole and 2 mixed histologies. The median age was 41.5. GTN samples were found to be PD-L1 positive (92.3%), tumor mutational burden (TMB) low (92.8%), and microsatellite stable (MSS) (100%). Forty-six percent of choriocarcinoma specimens contained a genomic alteration including TP53 (33%) and homologous recombination repair (HRR) (13%) genes. Alterations in RTK-RAS pathway signaling was present in 40% of ETT cases.

CONCLUSIONS

The high rate of PD-L1 positivity in this real-world database and reported in prior literature support continued clinical trial development evaluating immunotherapy for treatment of GTN. Other potential targeted treatments identified include Wee1, PARP and MEK inhibitors based on molecular alterations in TP53, HRR genes, and RTK-RAS pathways respectively.

Cross-individual cancer transmission to children during the gestational and perinatal periods

Cancer transmission may rarely occur between individuals. Besides through allogenic transplantation, cancer transmission via the hemochorial placenta, which is permissive for cell traffic, has been described in a few reports. Three etiologies of transplacental cancer transmission include (1) maternofetal transmission of maternal cancer cells, (2) transmission of gestational choriocarcinoma to the fetus, and (3) transfer of preleukemic cells from one monozygotic twin to the other. Additionally, we recently reported two pediatric cases of lung tumors in which the lung-only distribution of tumors and genomic profiling of both the child's and mother's tumor samples suggested the airway/transbronchial transmission of maternal cervical cancer cells to the child by aspiration at birth. The immune system coordinates the hemostatic balance between effector and regulatory immunity, especially during fetal development. The immunoregulatory properties are shared in both physiological pregnancy-related and pathological cancer-related conditions. Mechanistically, the survival and colonization of transmitted cancer cells within a child are likely attributed to a combination of the child's immune tolerance and the cancer's immune escape. In this review, we summarize the current understanding of gestational/perinatal cancer transmission and discuss the possible mechanism-based immunotherapy for this rare form of pediatric cancer.

Placental-site trophoblastic tumor with bone metastasis: A diagnostic and therapeutic challenge

Placental-site trophoblastic tumor (PSTT) is a rare pathological entity included in the spectrum of gestational trophoblastic neoplasia (GTN). It is a neoplasia with metastatic potential that, once metastasized, has poor prognosis because the tumor tends to be less sensitive to chemotherapy. We present a rare case of gestational trophoblastic neoplasia, in which hysterectomy for persistent gestational trophoblastic disease after hydatidiform mole, revealed a primary PSTT in the uterus. Subsequently, a slight persistent elevation of the beta fraction of human chorionic gonadotropin hormone (B-hCG) during follow-up revealed the presence of bone metastases. This location is not usual from this tumor, being even more rare the case of PSTT with isolated bone metastases. Metastasic foci were only identified with PET-CT since the usual diagnostic resources were not able to do it. Finally, it is also remarkable in our case that the treatment required the confluence of chemotherapy together with immunotherapy to achieve a favorable response.